Upper cylinder lubricant



Patented July 28,1942

Shailer L. Bass and Eldon F. Graves, Midland, Mich, assignors to TheLubri-Zol Corporation,

Wickliffe, Ohio, a corporation of Ohio lN'o Drawing.

6 Claims.

This invention relates, as indicated, to addition agents for internalcombustion engine fuels and more particularly to a method of lubricatingthe upper parts of such engines where extreme conditions of pressure andtemperature mayobtain. The addition agents of this invention areparticularly suited to this purpose by their unusual effectiveness,their stability at high temperatures, and the fact that they arenon-corrosive to metals under operating conditions. Further advantageswill appear as the description proceeds.

The necessity for adequate lubrication in the upper parts of internalcombustion engines has long beenapparent and various suggestions havebeen made for its assurance with equally varying success when carriedinto practice. When an engine is started there is generally little or nolubricant remaining on the walls of the upper cylinder and excessivewear takes place, especially in cold weather.. For this reasontop-oilers have been employed by many persons but with not toosatisfactory results.

The obvious method of introducing a lubricant to the upper parts of anengine is to employ the fuel as a vehicle and it is one of the objectsof this invention to provide an addition agent suited to such purpose.

Another object of this invention is toprovide a lubricant capable ofresisting the high operating temperatures of internal combustion enginesand of aifording adequate lubrication to the relatively moving partsunder conditions of extreme pressure.

A further object is to provide an addition agent which is unusuallyefiective even when employed in very minor amounts and to provide anengine fuel suitable for consumption by internal combustion engines andwhich has mixed therewith the addition-agent of this invention.

Still another object of this invention is to provide a lubricatingconstituent in the fuel acting to lubricate and keep clean the parts ofthe engine handling the fuel prior to combustion.

Application November 22, 1938, Serial No. 241,810

The following description sets forth in detail certain approvedcombinations of ingredients embodying our invention, such disclosedmeans constituting, however, but certain of various forms in which theprinciple of the invention may be used. 1

Broadly stated, this invention comprises a new I fuel and method oflubricating the upper parts of internal combustion engines, said fuelcomprising the usual liquid hydrocarbons, e. g., gasoline, Diesel fuel,etc., having a viscosity of below 50 sec. Saybolt Universal at 100 F.,and a minor amount of an ester of a phosphorus acid, preferably a liquidester. We have found that of these esters the aromatic esters ofphosphoric acid (aromatic phosphates) are the most effective whenemployed for the purposes of this invention and are therefore preferred.

Of the broad class of aromatic esters of phosphoric acid which may thusbe employed in accordance with our invention, the aromatic phosphatescontaining at least one aromatic radicle having a molecular weight of100 or more and preferably containing a polyphenyl radicle are generallysuperior. I

The aromatic esters of phosphoric acid, which term is intended toinclude the alkyl aryl esters, when compounded with the fuel, gasoline,for instance, are found to greatly increase the film strength of thefuel as determined by the wellknown Almen machine. The improvement thusaddition agent to produce a lubricating film of increased film strengthinasmuch as the film strength is not only greater than that of eitheralone but, also, a bearing will operate at lower torque for a givenbearing load than with either alone.

The following is a list of particularly efiective This problem isparticularly acute in Diesel 5 compounds together with theconcentrations in engines where the gumming of orifices and close- .lyfitting parts and the abrasive wear on such gasoline which aifordmaximum film strength:

Per cent by weight Phenyl di (o-chlor phenyl) phosphate 0.4 Phenyl di(o-xenyl) phosphate 0.5 Di-phenyl mono (o-xenyl) phosphate 0.6

Since compounds of the type herein disclosed are chemicallystable athigh temperatures, that is, up to 600-650 F., they are not corrosive tometals under the conditions obtaining in internal combustion engines inoperation. Also, the small quantities required are insufflcient tonecessitate any great correction of the carbureter, etc., nor do theyinjurlously affect the keeping qualities efiect. The abilityto-withstand high tempef tures without decomposition makes the compoundsof this invention particularly adapted for use in Diesel and aviationengines.

I as 0.1% to as much as 5.0%.

The word fuel as used in this application is intended to include theusual hydrocarbon fuels having a viscosity below 50 sec. SayboltUniversal at 100 F. and a flash point below 200 F. Such fuels will alsohave distillation points below those of the following table:

at 450 n. 90% at 600 F. End at 700" F.

and higher A. P. I. gravity values than 35.

-It is thought that the addition agents may chemically orphysico-chemically react with the metallic surfaces to form anon-welding surface at points of extreme pressure, thus preventingseizing and scoring with resultant disastrous wear.- It is not intended,however, that this invention should be limited by any explanation ortheory as to the reasons for the remarkable efficacy of the fuel of thisinvention.

In summary, the following are among the advantages of this invention: I

(1) The upper parts of the engine are effectively lubricated immediatelyupon the starting ing no enhanced deleterious eifects.

(.8) There isno corrosive effect upon metallic parts.

(9) The fuel'is easily prepared.

of the fuel in storage, often having a contrary Other modes of applyingthe .principle of our invention may be employed instead of the oneexplained, change being made as regards the materials employed, providedthe ingredients stated by any of the following claims or the equivalentof such stated ingredients be employed. a

We therefore particularly point out and distinctly claim as ourinvention:

1. As a new composition of matter,an internal combustion engine fuelcomprising a liquid hy-' drocarbon fuel having a viscosity below 50seconds Saybolt Universal at 100 F., the boiling range of thehydrocarbon content of which has remained substantially unaltered and towhich has been added from about 0.1% to about 5.0% by weight, based onthe amount of fuel, of a liquid'aromatic ester of 'phosphoricacidcontaining at least one aromatic radicle having a molecucombustionengine fuel comprising a liquid hy- (10) The fuel injector systems ofDiesel engines are kept clean and require fewer repairs.

drocarbon fuel having a viscosity below 50 seconds Saybolt Universal at100 vF., the boiling range of the hydrocarbon content of which hasremained substantially unaltered and to which has been added from about0.1% to about 1.0%

by weight, based on the amount of fuel, of phenyl di (o-chlor p'henyl)phosphate.

3. As a new composition of matter, an internal combustion engine fuelcomprising aliquid hydrocarbon fuel having a viscosity below 50 secondsSaybolt Universal at 100' F.,' the boiling range of the hydrocarboncontent of which has remained substantially unaltered and to which hasbeen added from about 0.1% to about 1.0% by weight, based on the amountof fuel, of phenyl di (o-xenyl) phosphate.

4. As a new composition of matter, an internal combustion'engine fuelcomprising a liquid hydrocarbon fuel, having a viscosity below' 50seconds Saybolt Universal at 100 F., the boiling range of thehydrocarbon content of which has remained substantially-unaltered and towhich has been added from about 0.1% to about 1.02% by weight, based onthe amount of fuel, of diphenyl mono (o-xenyl) phosphate.

5. An internal combustion engine fuel the-boiling range of thehydrocarbon content of which has remained substantially unaltered and towhich has been added from about 0.1% to about 5.0% of an aromaticester-of phosphoric acid containing a poly-phenyl radicle.

6. An internal combustion engine fuel comprising from about 99.9% of theusual hydrocarbon fuel and 0.1% of an ester of an acid of phosphorus toabout of such fuel and 5% of an ester of an acid of phosphorus.

SHAILER L. BASS. ELDON F. GRAVES.

